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Background As chronic atopic dermatitis (AD) is associated with activation of circulating and infiltrating monocytes, monocytes are considered to play a pivotal role in the establishment of chronic lesions in AD. Histamine is an important mediator of inflammatory and allergic responses. Although new immunomodulatory functions of histamine have recently become apparent, the effect of histamine on the life span of monocytes remains unclear. Objective In the present study, we investigated the effect of histamine on the life span of human monocytes from normal healthy donors and patients with AD. Methods Monocyte apoptosis was induced by serum deprivation, CD95/Fas ligation, or dexamethasone in the presence of histamine, and measured using annexin V-and propidium iodide-staining. Bcl-2 protein and activated caspase-3 were determined by flow cytometry. We also examined the effect of soluble, histamine-induced factors produced by monocytes on apoptosis. Furthermore, we examined whether monocytic apoptosis is dependent on the cAMP pathway. Results Histamine prevented monocytic apoptosis induced by serum deprivation, CD95/Fas ligation, or dexamethasone in a dose- and time-dependent fashion. The inhibitory effects of histamine on monocytic apoptosis were blocked by an H2R antagonist, and mimicked by an H2R agonist. Histamine also up-regulated the expression of Bcl-2 and Mcl-1, and inhibited the activation of caspase-3. The culture supernatants from histamine-treated monocytes inhibited monocytic apoptosis, which was partly reversed by the removal of IL-10. Monocytes cultured with anti-IL-10 mAb and histamine did not exhibit an inhibitory effect on apoptosis. The histamine-induced anti-apoptotic effect was attenuated when monocytes were cultured in the presence of a cAMP inhibitor. Conclusions These results indicate that the H2R signals induced by histamine allow monocytes to prolong their life span and infiltrate to the site of inflammation. This process may contribute to the establishment of chronic allergic disorders, such as AD. [ABSTRACT FROM AUTHOR]

Objectives: We previously reported a higher left atrial volume index (LAVI) was independently associated with left atrial (LA) appendage (LAA) thrombus formation in 737 patients with non-valvular atrial fibrillation (NVAF) receiving appropriate oral anticoagulation therapy. Since our previous study was a retrospective single-center study, we designed and conducted a prospective multi-center study to verify our findings for LAVI as a predictor of LAA thrombus in patients with NVAF receiving appropriate oral anticoagulation therapy., Methods: This prospective multi-center study comprised 746 consecutive patients with NVAF recruited between December 2021 and March 2023 from eight institutions in Japan, who were receiving appropriate oral anticoagulation therapy, had undergone transthoracic echocardiography and transesophageal echocardiography (TEE)., Results: LAA thrombi were observed in 21 patients (2.8%). The prevalence of LAA thrombus formation in patients with paroxysmal AF (PAF) was significantly lower than that in patients with non-PAF (0.7% vs. 4.1%, p = .006). LAA thrombus formation was detected in none (0/171) of the patients with normal size LA (LAVI ≤ 34 mL/m 2 ). The prevalence of LAA thrombus formation in patients with mildly dilated LA (LAVI: 34-49.9 mL/m 2 ) was 2.1% (6/283), but that in PAF patients was low at 1.0% (1/104). Furthermore, this prevalence in patients with severely dilated LA (LAVI ≥ 50 mL/m 2 ) was high at 5.1% (15/292)., Conclusions: The findings of this prospective multi-center study are consistent with those of our previous study. Thus, the need for TEE prior to catheter ablation or electrical cardioversion can be determined by the level of LAVI., (© 2024 Wiley Periodicals LLC.)

Objectives: Our aim was to test the hypothesis that comprehensive simplified left atrial (LA) assessment derived from routine echocardiography may be more useful than assessment of LA volume alone for predicting atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI)., Methods: We studied 156 patients with paroxysmal AF (PAF) who had undergone PVI. Echocardiography was performed within two days before PVI. Maximum (Max-LAVi) and minimum LA volume index (Min-LAVi) were calculated with the biplane modified Simpson's method, and then normalized to the body surface area. On the basis of previous findings, the predefined cutoff value of Max-LAVi for AF recurrence was set at Max-LAVi ≥ 34 mL/m 2 . ΔLA volume index (ΔLAVi) was also calculated as Max-LAVi minus Min-LAVi. The follow-up period after PVI was 24 months., Results: AF recurrence was observed in 35 patients. Multivariate logistic regression analysis showed that ΔLAVi (odds ratio [OR]: 1.131; 95% confidence interval [CI]: 1.057-1.221; P < 0.001) was an independent predictor of AF recurrence. Sequential logistic regression models for predicting AF recurrence revealed that a model based on clinical variables including age, gender and AF duration (χ 2  = 1.65) was improved by the addition of Max-LAVi ≥ 34 mL/m 2 (χ 2  = 13.8; P < 0.001), and further improved by the addition of ΔLAVi (χ 2  = 18.2; P = 0.036). Of note is that only 1.02 ± 0.10 minutes per patient was needed to obtain a comprehensive LA assessment that included Max-LAVi, Min-LAVi, and ΔLAVi., Conclusion: This easy-to-use comprehensive simplified LA approach from routine echocardiography may well have clinical implications for better management of PAF patients., (© 2019 Wiley Periodicals, Inc.)

Objectives: Pulmonary hypertension (PH) is characterized by marked and sustained elevation of pulmonary vascular resistance and pulmonary artery pressure, and subsequent right-sided heart failure. Right ventricular (RV) function and exercise capacity have been recognized as important prognostic factors for PH. Our aim was to investigate RV contractile reserve and exercise capacity during a leg-positive pressure (LPP) maneuver., Methods: The study population comprised 43 PH patients and 17 normal controls. All patients underwent echocardiography at rest and during LPP stress. Exercise capacity was assessed by 6-minute walk distance for PH patients. RV relative wall thickness was calculated from dividing by RV free wall thickness by basal RV linear dimensions at end-diastole. RV function was calculated by averaging peak speckle-tracking longitudinal strain from the RV free wall. RV contractile reserve was assessed as the difference in RV free wall strain at rest and during LPP stress. Changes in left ventricular stroke volume (ΔSV) during LPP stress were also calculated., Results: ΔSV and RV contractile reserve of PH patients were significantly lower than of controls (3.6 ± 6.0 mL vs 8.5 ± 2.3 mL, and 8.2 ± 11.9% vs 14.5 ± 6.6%; both P < 0.01). RV contractile reserve of PH patients with ΔSV <3.3 mL was significantly lower than of PH patients with ΔSV >3.3 mL (3.9 ± 13.2% vs 12.3 ± 8.9%; P = 0.02). ΔSV had also significant correlation with 6-minute walk distance (r = 0.42, P = 0.006). Multivariate regression analysis showed that RV relative wall thickness was an independent determinant parameter of ΔSV during LPP stress for PH patients (β = 3.2, P = 0.003)., Conclusions: Preload stress echocardiography in response to LPP maneuver, a noninvasive and easy-to-use procedure for routine clinical use, proved to be useful for the assessment of RV contractile reserve and exercise capacity of PH patients., (© 2018 Wiley Periodicals, Inc.)

We present optimally reconstructed three-dimensional computed tomography images of left ventricular outflow obstruction, comprehensive left ventriculography, and comparable intraoperative transesophageal echocardiography, as well as serial operative pictures, to facilitate the understanding of live-heart anatomy of hypertrophic obstructive cardiomyopathy. As shown in this case, detailed morphological analysis around the left ventricular outflow tract using preoperative computed tomography would be feasible and useful. The present case highlights the importance of obtaining complete three-dimensional information present in the acquired computed tomography dataset because computed tomography is not entirely noninvasive or free of radiation exposure and contrast material., (© 2018 Wiley Periodicals, Inc.)